Farmers who are familiar with using light-deprivation techniques to increase crop yield are also familiar with the struggle and great effort that comes with pulling heavy blackout tarps over their crops twice or four times daily. With the disclosed device, sometimes referred to as a tarp puller, the process of covering or uncovering any length greenhouse can be accomplished in just a few minutes. Typically, the canopy hoist comprises a set of two heavy-duty galvanized steel units. With one installed on each side of the greenhouse, the task can be completed quickly and with much less effort by just one person.
In the disclosed embodiment, telescoping steel tubing as part of the arm can be adjusted to fit typical greenhouse sizes such as 20 feet wide and 10′ tall, but can also be used on much larger greenhouses such as 40 feet wide by 140 feet long by 18 feet tall by increasing the length and other dimensions of the canopy hoist, as would be apparent to those skilled in the art. The tarp puller consists of two heavy duty pivoting steel arms. Each arm is mounted to approximately two cubic feet of concrete at either end of the greenhouse and can be assembled and install with simple hand tools.